This invention relates to fluid control valves, used to control the flow of liquids and/or gases, and in particular to apparatus for guiding a valve operating member such as a valve stem.
Fluid control valves, such as, for example, stem valves, typically include a valve body containing a valve seat, a valve plug attached to a movable valve stem, and an actuator mechanism for moving the valve plug via the valve stem. Typically, at least one bushing is used to assist in guiding the valve stem. However, U.S. Pat. No. 5,791,629, assigned to the same assignee as herein, discloses a fluid control valve that does not use any bushings to guide the valve stem. Instead, a pair of packing sets provides a sufficient stem guidance, interference fit with the valve stem to enable the usual upper and lower metal guide bushings to be eliminated.